Wednesday, October 2, 2013

Diabetes, Drugs, and Cardiovascular Risk

The October 3 New
England Journal features a “Perspectives” written by Drs. William R. Hiatt,
Sanjay Kaul, and Robert J. Smith, all members of the FDA Endocrine and
Metabolic Drugs Advisory Committee:http://www.nejm.org/doi/full/10.1056/NEJMp1309610

The basic thrust of their piece is to defend the drug
rosiglitazone (Avandia) from the accusations we’ve reviewed widely in this
blog, that it causes excess cardiovascular risk. These authors appear to
believe that when all the data are in, the risk has been overblown. (According
to the on-line disclosure forms, two of the three have some financial ties to
the drug industry, but this group does not appear to be overloaded with
conflicts of interest so far as I can tell.)

They then proceed to discuss two newer diabetes drugs that
have been subjected to extra scrutiny by the FDA, which is now gun-shy over
diabetes drugs since the Avandia affair.These newer drugs also appear to be reasonably safe in terms of not
causing excess cardiovascular risks. But the flip side of that was that neither
drug decreased cardiovascular risks, either, as one would hope for from a drug
that treated a condition that is a major cause of cardiovascular disease.

In previous posts I have hammered on about one of the major
consequences of drug industry marketing on diabetes:

http://brodyhooked.blogspot.com/2012/04/yet-more-on-broken-disease-model-of.html
--which is the promulgation of a flawed disease model among
both practicing docs and the general public. We now have a lot of evidence that
Type 2 (adult) diabetes should not be viewed primarily as
“high blood sugar,” that drugs that lower blood sugar very well may be useless
for preventing the downstream complications of diabetes. Yet drug industry and
device marketing still finds the big bucks in pushing tight sugar control and
close sugar monitoring.

So I find it worthwhile noting these passages in the
“Perspective” by Drs. Hiatt, Kaul and Smith, and if they have financial ties to
companies that make diabetes drugs, these passages are all the more impressive:

“From a
cardiovascular perspective, rosiglitazone, saxagliptin, and alogliptin appear
to be relatively safe. It is disappointing, however, that neither intensive
glycemic control nor the use of specific diabetes medications is associated
with any suggestion of cardiovascular benefit. Thus the evidence does not
support the use of glycated hemoglobin as a valid surrogate for assessing
either the cardiovascular risks or the cardiovascular benefits of diabetes
therapy….New therapies
targeting glycemic control may have cardiovascular benefit, but this has yet to
be shown. The optimal approach to the reduction of cardiovascular risk in
diabetes should focus on aggressive management of the standard cardiovascular
risk factors rather than on intensive glycemic control.”

Let me translate a bit: Drugs that lower blood sugar have
not yet been shown to prevent heart and blood vessel disease in adult-type
diabetes. Treating Type 2 diabetes today should focus on proven methods for
preventing such diseases, which is to lower cardiovascular risk factors. Simply
showing that a drug lowers blood sugar says nothing about its value for
preventing the serious complications of diabetes and should not be accepted by
the FDA as a reason to market a new drug. And there you have it, from the
(supposed) experts.